Kira Himuro is a character from the anime Marginal #4 the Animation and is a member of the idol unit Lagrange Point, who serve as the senior group to the titular Marginal #4. Standing at 179 centimeters tall with a weight of 63 kilograms and a blood type B, Kira has a birthday on May 5. He is characterized by his blue eyes and gray hair, which often has a distinctive streak, contributing to his bishounen appearance.

Personality-wise, Kira is best described as a cheerful and caring individual. He is notably good at taking care of others and often takes on the role of a mentor. This is particularly evident in his interactions with the younger members of Marginal #4, as he frequently takes it upon himself to guide and teach his inexperienced juniors. His demeanor is often compared to that of a sun prince, exuding a bright and wild, self-assured atmosphere. Despite his generally sunny disposition, he is not without flaws; Kira also possesses a crude or rough side to his personality that emerges on occasion.

Kira is one half of the idol duo Lagrange Point, his partner being Shy Makishima. While his partner is described as stoic and somewhat proud, Kira serves as the more outwardly cheerful and approachable counterpart. Together, Lagrange Point aims for the big stage, sharing the same goal of scattering stars as their junior group. Kira is depicted as a key figure within the agency, holding a position that commands respect from the newer idols. He is described as a sun prince who helps the main group shine, with his role being central to guiding their development. The key to making all the idols, including Kira, truly shine is their manager, Yue Kataoka.